Speedometer.



sennnolan'rne.

'To allwiom it may concern.'

Be it lknown that l, Een C. OLIVER, a citizen of the United States, residing at De troit, county ot Wayne, State of Michigan, have invented a certain new and useful lmprovement in Speedometers, and declare the following to he a full, clear, and exact description of the same, such es will enable others skilled in the nrt to which it pertains to make and use the same, reference being' had to the accompanying drawings, which form a part of this specification. d,

My invention relates to the method of constructing speedometers and the speedoineters constructed by this method, and the object lof my improvements is to provide for the cheap and convenient construction of a speedometer and to an improved speedometer inwhich friction is reduced and the movement of the indicating pointer shell he always proportional to the speed indicated.

.and 3. Fig. 3, is e section on the line` of Fig. looking from the thereto.

I accomplish this object in the device illustrated in the accompanying drawing, and constructed by the method hereinafter described.

In the accompanying drawing :-Figure 1,

is an elevation of a speedometer showing equal graduations of the scale, and the' pointer adapted. to indicate a speed by its 'position on said scale. Fig. 2, is a section in a plane perpendicular to the plane passing approximately through the center of the device, as indicated hy lines 2--2 in F l right ol the section. piene. Fig. 4, is a detail View showinlgr4 asupporting plate, and some of the .mechanism of lthe speedometer.

A, Agis the casing of e speedometer.

l', is the face plate upon .which are the -gradoationfs ot the seele E.

C, is e shaft carrying a pointer l, which moves overthe scaie E, to indicate the speed.

F, is a. sheft mounted in hearings in the frame a4-a, secured in the casing,l A, A. ihe shaft F is to he connected tothe ohject, the speed'ofvvhich is to he measured so that said shafiit` 'shall loe rotated at a rate pro-- portional to the speed oteaid ohjiect.

G, indicates an annulus. pivoted upon e shaft H, which shaft extends at right angles from the shaft F and is rigidly secured The annulus G surrounds the shaftsF and H and is normally in a plane forming an ecute angle With the shaft F, as' indicated in Fig. 2.

eciceton of Letters etent. Application filed August 22, ESM?. Serial No. tiLSlS.

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S1, is a hole bored through the periphery ot' the annulus G and central thereto.

d, is a tension spring secured e on the annulus G at its inner end to a to apintle its outer end and at lug f, secured to the shaft F. The lug f is so located that the spring a?, shall act hy its tension to turn the annulus G toward the plane of the axis of the shaft l?. The shaft is bored out to form an open ing extending in from one end thereof, and is pivotcd with a slot J through its Wall.

i, is a rod fitting and adapted to slide in the opening in the shaft F.

T, is a rod extending at right angles from the rod l. through the slot S, .is a cam extending from the ece'o the nnnulus G at right angles thereto, and in a plane through the center ot seid annu'lus and in position to contact the rod T.

' l is a projection formed by .a slot cut in the outer edge of the cam S. The outer edge 't the projection slforins a continuation of the acting edge of the cam S.

M', L, are the two arms of a bell crank lever pivoted upon a supporting plate Z at K.

N, is a raclr formed in the are of a circle, the center oit' which is at the pivot of the lever M, L. A

P, is a gear Wheel on the shaft C, the teeth of the rack N engaging those of the gear Wheel P.

Q, is en erin extending approximately et right angles from the arm hl.

it, isa lug,Y extending rointhe hearing' plate Zi.

53p, is a tension spring, one end of which is secured to the lug t and the other end to the outer end ci the arm Q, the tension of the spring` Sp tends to turn the hell crank lever M, L, to the position shown in Fig. 4, which the rack N has acted uponthe gear wheel P to tarn it to its zero position. The arm L may carry a friction roller at its outer end y, Where it engages against-the end of the rod l, as shown in Figs. 2 and.

The method ofconstructing end the ope eration of follows: "idhen the shaft I+" is rotated, een; trifogal :ce ects to turn the annulns G about its pivot on the shaft ll, toward a po sition in a plane 'at right angles to said Shaft. This force is 'balanced by the tension of the spring d at each point. As the plane of the ennulus G changes when impelled by centrifugal force, the face of the cam S acts on. the rod T to move the rod I longitudithe abovedescrihed device is as or no sliding so that friction heretofore incident to the action of these cams is largely obviated. The surfaces are formed approximately to shape, and the rod T and projection s are made narrow and flexible enough i so that they may be bent to secure the proper contour of the acting surfaces.

To secure the proper relation between the movements of the parts and the graduations of the scale, I cause the shaft F to rotate at a known speed and note the position of the parts at this speed. I then take hold of the rod 'I with. a pair of pliers and bend. it to a shape that shall cause a corresponding movement of the pointer D. This may be done for a number of points and thus the proper contour of the rod T may be easily obtained.

Experience has taught, that toward the outer portion of the cam S, its edge or wiper face frequently requires adjusting, I therefore slot the cam S to secure the projection s, which may be formed by bending with a. pair of pliers, as above described, with reference to the rod T.

1. The combinationwith the index hand of a speed measure, of two members having contactingv surfaces one of which is the lat- 'cral surface of a-.rod" of sufficient rigidity to maintain its shape in the ordinary use of the. instrument but sufficiently flexible to be readily bent so as to vary the' longitudinal contour of said surface, means connecting said members with said index hand adapted to transmit motion from the fermento the latter. M

2. The combination with the index hand of a speed measure, of positioning means therefor including two members having contacting surfaces, one of which isthe lateral surface of a rod of sufficient rigidity to maintain its chape in the ordinary use of the instrument but sufficiently flexible to be readily bent so as to varythe longitudinal contour of saidsurfacc, whereby the indications of the instrument may be rectified.

In testimony whereof, I sign this specification in the presence of two witnesses.

y EDD C. OLIVER.

Witnesses:

Lor'rA LEE BRAY, ELLio'r'r J. S'roDDAnD. 

